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a bitter alkaloid extracted from chinchona bark; used in malaria therapy

a bitter alkaloid extracted from chinchona bark; used in malaria therapy

An alkaloid derived from the bark of the cinchona tree. It is used as an antimalarial drug, and is the active ingredient in extracts of the cinchona that have been used for that purpose since before 1633. Quinine is also a mild antipyretic and analgesic and has been used in common cold preparations for that purpose. It was used commonly and as a bitter and flavoring agent, and is still useful for the treatment of babesiosis. Quinine is also useful in some muscular disorders, especially nocturnal leg cramps and myotonia congenita, because of its direct effects on muscle membrane and sodium channels. The mechanisms of its antimalarial effects are not well understood.

A bitter drug obtained from the bark of the Cinchona tree.

White alkaloid of cinchona, very bitter taste; tonic, stimulant, antiperiodic.

An alkaline substance, obtained from the bark of the Cinchona tree, much used in medicine in the treatment of agues and fevers.

Medicinal alkaloid obtained from the bark of the cinchona-tree.

An alkaline, uncrystalliznble substance; under the form of a porous, whitish mass; almost insoluble in water, soluble in alcohol and ether. It forms, with acids, salts that are in general soluble. It is obtained from different cinchonas, but chiefly from the yellow, and is the active principle of those valuable drugs.

The salt usually employed in medicine- occurs in needles of a pearly and satiny appearance. It is employed with great success in the treatment of intermittents; and is available in many cases, where the bark in substance could not be retained, or would be injurious. Dose, as a tonic from 3 to 10 grains in the 24 hours. As an antiperiodic it may be carried much farther. Its action, in a large dose, is decidedly sedative. It is obtained, by treating the yellow bark with sulphuric acid. The following form is adopted in the Pharmacopoeia of the United States. Boil the bark in one- third of the water mixed with one-third of the muiriatic acid, and strain through linen. Boil the residue twice successively with the same quantity of acid and waiter as before, and strain. Mix the decoctions, and, while the liquor is hot, gradually add the lime, previously mixed with two pints of water, stirring constantly, until the quinia is completely precipitated. Wash the precipitate with distilled water, and having pressed and dried it, digest it in boiling alcohol. Pour off the liquor and repeat the digestion several times, until the alcohol is no longer rendered bitter. Mix the liquors, and distil off the alcohol, until a brown viscid mass remains. Upon this substance, removed from the vessel, pour about half a gallon of distilled water, and having heated the mixture to the boiling point, add as much sulphuric acid as may be necessary to dissolve the impure alkali. Then add an ounce and a half of animal charcoal; boil for two minutes; filter the liquor while hot, and set it aside to crystallize. Should the liquor, before filtration, be entirely neutral, acidulate it very slightly with sulphuric acid. Should it, on the contrary, change the colour of litmus paper to a bright red, add more animal charcoal. Separate the crystals from the liquor, dissolve them in boiling water slightly acidulated with sulphuric acid, add a little animal charcoal, filter and set aside to crystallize. Wrap the crystals in bibulous paper, and dry with a gentle heat. The mother- waters maybe made to yield an additional quantity of sulphate of quinia by precipitating the quinia with solution of ammonia, and treating the precipitated alkali with water, sulphuric acid, and animal charcoal, as before.

n. [Spanish] A basic alkaloid obtained from various species of cinchona or Jesuit's bark ;- one of the salts of quinine, especially the sulphate used as a tonic and febrifuge.